<!DOCTYPE html>
<html lang="zh-CN">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>全屏图片展示</title>
  <style>
    html, body {
      height: 100%;
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      width: 100vw;
      height: 100vh;
      overflow: hidden;
      position: relative;
    }
    .original-img {
      position: fixed;
      top: 0;
      left: 0;
      width: 100vw;
      height: 100vh;
      max-width: 100vw;
      max-height: 100vh;
      object-fit: cover;
      z-index: 2;
      border-radius: 0;
      box-shadow: none;
    }
    .back-btn {
      position: fixed;
      top: 24px;
      left: 24px;
      z-index: 3;
      background: rgba(0,0,0,0.5);
      color: #fff;
      border: none;
      border-radius: 6px;
      padding: 10px 18px;
      font-size: 16px;
      cursor: pointer;
      transition: background 0.2s;
    }
    .back-btn:hover {
      background: rgba(0,0,0,0.7);
    }
    @media (max-width: 600px) {
      .original-img {
        max-width: 98vw;
        max-height: 60vh;
      }
      .back-btn {
        top: 10px;
        left: 10px;
        font-size: 14px;
        padding: 8px 14px;
      }
    }
  </style>
</head>
<body>
  <button class="back-btn" onclick="window.history.back()">返回</button>
  <img class="original-img" src="../images/苏震项目管理系统.png" alt="原图">
</body>
</html>
